In order to guide a catheter to a target site of a living body lumen, such as a digestive tract or a blood vessel, a guide wire is used when inserting the catheter into the living body lumen. The guide wire is used in this manner in a position in which it is inserted into the catheter. For example, during observation or treatment of a target site using an endoscope inserted into a living body lumen, a guide wire is used in order to guide a catheter inserted into the endoscope or a lumen of the endoscope to the target site.
Known guide wires, such as disclosed in JP-A-2008-307367 and WO2011/118443, have an elongated wire body, a resin coating layer covering a distal portion of the wire body and an annular member arranged on a proximal side of the resin coating layer. In these guide wires, a proximal outer diameter of the resin coating layer and a distal outer diameter of the annular member are provided in order to help prevent turning up of the resin coating layer, but further measures to help prevent turning up of the resin coating layer are needed.